Microbial Community Structure Of Traditional Fermentation Starters For Hong Qu Glutinous Rice Wine And Analysis Of Volatile Flavors Produced By Microbe

Monascus rice wine is one of the characteristics of yellow rice wine in China.Monascus rice wine brewing technology is unique.Because of its bright color,mellow taste and rich aroma,it is deeply loved by the masses and red yeast rice wine in different regions because of the use of different traditions.The different brewing starters and different brewing processes will lead to significant differences in the final product flavor quality,and studies have shown that this is closely related to brewing microbes.In this paper,the high-throughput sequencing technology and head space solid-phase extraction-gas chromatography-mass spectrometry(HS-SPME-GC/MS)technology were used to analyze the difference in the microbial community structure and volatility of different types of starters in Hongqu rice wine.Material differences reveal the mechanism of red yeast rice wine fermentation,which lays a foundation for improving the flavor quality of red yeast rice wine and improving the traditional brewing process of red yeast rice wine.The main research contents and results are as follows:(1)High-through put sequencing techniques were used to analyze and compare traditional fermentation starters for Hong Qu glutinous rice wine and heatmap were used to identify dominant microbial community,which provides a theoretical basis for the further explore microbial community structure traditional fermentation starters for Hong Qu glutinous rice wine.The result show that there appeared to be no statistically significant difference regarding the diversity indices and species richness between the two types of wine starters-Hong Qu and Yao.However,the dominant microbial community of Hongqu are uncultured bacterium,Bacillus ginsengihumi,Pantoea sp.,Elizabethkingia sp.,Streptococcus sp.,Psychrobacter sp.,Brevundimonas sp.,Monascus purpureus,Aspergillus nigec Xeromyces bisporus,Aspergillus penicillioides,Aspergillus flavus.The dominant microbial community of Yaoqu are uncultured bacterium,paramesenteroides,Lactobacillus fermentum,Gluconobacter thailandicus,Streptococcus sp.,Lactobacillus alimentarius,Rhizopus arrhizus,Saccharomycopsis fibuligera,Aspergillus niger;Xeromyces bisporus,Issatchenkia orientalis and Saccharomycopsis malanga.(2)An analysis of volatile metabolite in different types of traditional fermentation starters for HongQu glutinous rice wine was performed by SPME-GC-MS.The assessment allowed the identification of 118 volatile compounds,mainly including esters(32),alcohols(22),acids(23),aldehydes(9)andketones(15)and the principal component analysis was used to find out the characteristic aroma substances and to explore the connection between microorganisms and volatile flavor substances in different types of traditional fermentation starters for HongQu glutinous rice wine by network-related analysis.(3)The difference of volatile metabolite in Hong Qu glutinous rice wine for used different types of traditional fermentation starters was screened by head-space solid-phase micro-extraction-gas chromatography-mass spectrometry(HS-SPME-GC/MS),principal component analysis(PCA)and orthogonal partial least squares(OPLS-DA).It was found that the dominant contribution for the formation of volatile compounds in HongQu glutinous rice wine is Hongqu,while the contribution of Yaobaiqu was less important than the contribution of volatile compounds in HongQu glutinous rice wine,But adding Yao Bai qu can significantly increase the content of the characteristics aroma components of HongQu glutinous rice wine.